chore(monorepo/client): move client source files

apps/client/src/widgets/llm_chat_panel.ts

@@ -0,0 +1,7 @@
+/**
+ * LLM Chat Panel Widget
+ * This file is preserved for backward compatibility.
+ * The actual implementation has been moved to the llm_chat/ folder.
+ */
+import LlmChatPanel from './llm_chat/index.js';
+export default LlmChatPanel;